Researchers at the Johns Hopkins Bloomberg School of Public Health's Center for a Livable Future calculated the nutritional value of food wasted in the U.S. at the retail and consumer levels, shining a light on just how much protein, fiber and other important
nutrients end up in the landfill in a single year.

These lost nutrients are important for healthy diets, and some -- including, dietary fiber, calcium, potassium and vitamin D -- are currently consumed below recommended levels. Nutrient-dense foods like fruits, vegetables, seafood and dairy products are wasted
at disproportionately high rates.

Previous research estimated that as much as 40 percent of food is wasted nationally, but it wasn't clear before this study how nutritious that food was. While not all wasted food is consumable, a sizeable amount is, leaving researchers and policymakers looking
for ways to minimize the amount of good food that gets tossed as millions of Americans go hungry, do not get enough nutrients or do not have access to healthy food options. The U.S. Department of Agriculture (USDA) and Environmental Protection Agency
have set a goal of reducing food waste by 50 percent by 2030.

The findings appear online in the Journal of the Academy of Nutrition and Dietetics, Chicago.

"Huge quantities of nutritious foods end up in landfills instead of meeting Americans' dietary needs," says study lead author Marie Spiker, MSPH, RD, a CLF-Lerner Fellow at the Johns Hopkins Center for a Livable Future and a doctoral candidate in the
Bloomberg School's Department of International Health. "Our findings illustrate how food waste exists alongside inadequate intake of many nutrients."

For their study, the researchers calculated the nutritional value of the retail- and consumer-level food waste of 213 commodities in 2012, using data from the USDA's Loss-Adjusted Food Availability data series. The research team, looking at 27 nutrients in all,
found that food wasted in the U.S. food supply that year contained 1,217 calories, 33 grams of protein, 5.9 grams of dietary fiber, 1.7 micrograms of vitamin D, 286 milligrams calcium and 880 milligrams potassium per person, per day.

Nutrient loss estimates provided by this study could contribute to a baseline for measuring future progress, the authors say.

The study also highlights how the amount of nutrients lost to waste compares to nutritional deficits in the typical American diet. For example, dietary fiber is important for maintaining digestive health and is found in grains, vegetables and fruits. Researchers
estimate that, in 2012, food wasted each day contained upwards of 1.8 billion grams of dietary fiber, which is comparable to the full recommended intake for dietary fiber for 73.6 million adult women. American women under-consumed dietary fiber by 8.9
grams per day in 2012. The study found that the daily amount of wasted dietary fiber is equivalent to the amount needed to fill this nutritional gap for as many as 206.6 million adult women.

Many factors contribute to food waste at both the retail and consumer levels, including the disposal of food due to aesthetic standards, large portion sizes, and management of perishables in fridges and pantries. There is currently great energy around efforts to
address waste of food. Preventing waste at the source is considered to be the optimal approach. Strengthening food recovery efforts that bring surplus food to food banks and pantries is also an important area of effort, innovation and impact.